Clamps for attaching earth entering elements to driving elements



Jan. 4, 1966 c. L. GUlLD ETAL CLAMPS FOR ATTACHING EARTH ENTERIN G ELEMENTS TO DRIVING ELEMENTS 10 Sheets-Sheet 1 Filed Aug. 9, 1962 M 4 8 5 a 7 f 5 7 f Mu 2 /o 7 m E E E Y r 6 3 oo 6 5 9 3 7 3 8 & w 4/3 7 0 9 4 8 6 u 3 e a 8 4 vog 3 W 47.8 a 0 7 0 A 5 5 3 3 e. 8 8 7 O U a &B D a w a x Jan. 4, 1966 c. L. GU

CLAMPS FOR ATTACHING A R o F sm D M M & 9 6 1% A uw a i JF c. L. GUILD ETAL 3,227,483 TTACHING EA ENTERING ELEMENTS TO DRIVING L MENTS o Sh t sn t 5 Jan. 4, 1966 c. L. GUILD ETAL 3,

CLAMFS FOR ATTACHING EA ENTERING ELEMENTS TO DRIVING MENTS Filed Aug. 9, 1962 10 Sheets-Sheet 5 lg /35 93 ga 94 87 ETA 3,227,483

ENTERING ELEMENTS EMENTS 10 Sheets-Sheet 6 Jan. 4, 1966 c. GUILD CLAMPS FOR ATTACHING EARTH TO 'DRIVING Filed Aug. 9, 1962 Jan. 4, 1966 c. L. GUILD ETAL 3,227,483 CLAMPS FOR ATTACHING EARTH ENTERING ELEMENTS TO DRIVING ELEMENTS Filed Aug. 9, 1962 10 Sheets-Sheet 8 Inveos: M i

I Jan. 4, 1966 c. L. GUILD ETAL 3,227,483

CLAMPS FOR A CH R'I'H ENTERING ELEMENTS DR ELEMENTS Filed Aug. 9, 1962 10 Sheets-Sheet 9 C. L. GUILD ETAL CLAMPS FOR ATTACHI Jan. 4, 1966 NG EARTH ENTERING ELEMENTS TO DRIVING ELEMENTS lO Sheets-Sheet o Filed Aug. 9, 1962 United States Patent O 3,227,483 CLAMPS FOR A'ITACHING EARTH ENTERING ELEMENTS TO DRIVING ELEMENTS 'Charles L. Guild, Rumford, R.I. (90 Water St., East Providence, R.I.), and Willard B. Goodnan, 13519 Cheltenlam Drive, Sherman Oaks, Qalif.

Filed Aug. 9, 1962, Ser. No. 216,948 16 Cl'aims. (Cl. 294-88) The present invention relates to clamps, each particularly adapted for use in attaching an earth entering element to the member by which it is driven or removed, the member being connected to a vibration generator, where the frequencies of the generated vibrations are in the subsonic or sonc ranges. The present application is a continuation-in-part of our copending application, Serial No. 160,442, filed December 19, 1961, now abandoned.

While the invention is adapted for use with any type of earth entering member of which Wall casings, pipes, and piles are typical examples, and with other types of driving and removing means, it is herein discussed primarly with reference to the driving of piles or their withdrawal as illustrative of the problems involved. When the driving or removal of such an element is effected by vibrations at frequencies in the above referred to ranges, it is necessary that it be clamped to the driving member to ensure the proper transmission of the cyclic forces for driving or withdrawing it. Such elements vary considerably as to their cross-sectional dimensions and the fact that one type commonly used is tubular and piles, in particular, are available in several diiferent crosssectional shapes. As a consequence, the use, under practical conditions, of such piles or other earth entering elements requires clamping means that are capable of securely supporting their large weights and of withstanding the large forces exerted in their driving or withdrawal, without being so heavy and cumbersome as to interfere with efficiency.

A principal objective is to provide locking means for locking an earth entering element to a mandrel without regard to the nature of the actuating means therefor, such locking means including a series of wedges arranged and disposed to be forced outwardly on upward movement of the means relative thereto thus to engage exposed wall portions of the element and distort them against the backing portion, the wedges being held in place relative to the hacking portion by retaining means. Another principal objective of the present invention is to provide a clamp having an upper housing section, typically a tubular mandrel extension, and a lowerdownwardly opening, receiver or body section for freely receiving the upper end of the earth entering element within it and providing the hacking portion. A double-acting ram within the housing section has a ram head within the receiver section. A series of wedges are provided for the ram head and these and the ram head have upwardly and inwardly inclined, mutually engaged surfaces by which the wedges are slidably supported for vertical movement relative to the ram head thus to efect outward movement of the wedges from inner positions thereof on upward movement of the ram head relative to the wedges, thereby to distort the earth entering element against the receiver. The wedges, in their inner positions, enter the element and as the element end enters the receiver section.

Another objective of the present invention is to provide a double-acting ram for use in actuating the means by which a pile or other earth entering element is locked to a mandrel without regard to the nature of such locking means. In accordance with this objective, a double-acting ram includes a piston having a stem provided with an axial passage extending from end-to-end thereof 3,Z27,483 Patented Jan. 4, 1966 through which extends a bolt by which the ram head is loosely connected to the stern, the connection between the ram head and the stem enabling universal angular adjustments of the head relative to the stem to be made as required.

Yet another objective of the invention is to provide a double-acting ram in which there is an upper housing section and a lower housing section and the cylinder of the double-acting ram is within the upper section and has a flange clamped between the sections. In detail, such a cylinder has a closed upper end and an open lower end, the piston has a stem slidably guided by the upper cylinder end and by the cylinder head which is clamped, along with the cylinder flange, between the housing sections.

A further objective of the invention is to provide first and second conduits each extending through the lower housing section with one opening into the cylinder below the piston and the other opening into the cylinder above the piston. Vents are provided that open into the cylinder above and below the piston thus to enable the cylinder to be vented. While usually the ram is actuated by oil under pressure, combustion of fluids and liquids may be used. The conduits may be detachable with respect to sources and, if so, it is preferable that each has a fitting, including a manually operable shut-off valve and a part for detachable elements by which each conduit may be coupled to a source of fluid under pressure.

Another objective of the invention is to provide means positively withdrawing the wedges from engagement with the earth entering element when it is desired to release the driving element therefrom.

Yet another objective of the invention is to provide means to enable each clamp to be used with a range of piles or other earth entering elements that differ one from the other with respect to their cross-sectional dimensions.

In the accompanying drawings, there is shown an illustrative embodiment of the invention from which these and other of its objectives, novel features, and advantages will be readily apparent.

In the drawings:

FIGURE l is a longitudinal section of a clamp in accordance with the invention for use with a pile of circular section,

FIGURES 2 and 4 are sections taken respectively, along the indicated lines 2--2 and 4-4 of FIGURE 1,

FIGURE 3 is a section taken along the lines 3-3 of FIGURE 2,

FIGURE 5 is a vertical section through a wedge provided with a shim,

FIGURE 6 is a View, similar to FIGURE l, illustrating a modification thereof,

FIGURES 7 and 8 are sections taken, respectively, along the indicated lines 7-7 and 8-8 of FIGURE 6,

FIGURE 9 is a fragmentary section, on an increased scale, showing one of the bolts interconnecting the housing and receiver sections,

FIGURE 10 is a partly sectionedview, on an increased scale, of the valve controlled liquid supply fittng,

FIGURE lOA is a section taken approximately along the indicated lines 10A-10A of FIGURE 10,

FIGURE 11 is a View, similar to FIGURES 1 and 6 but illustrating an embodiment of the invention for use with a pile that is H-shaped in cross section,

FIGURES 12 and 13 are sections taken substantially along the indicated lines 12-12 and 13-13, respectively, of FIGURE 11, and

FIGURE 14 is a bottom view of the clamp shown in FIGURES 11-13.

In the embodiment of the invention shown in FIG- URES 1 through 5, the mandrel extension of the driving element is generally indicated at 10. The mandrel extension is a tubular housing section of the clamp and is provided with an outwardly disposed flange 11 at its lower end.

A clamp body or receiver section 12 is secured to the flange 11 as by cap screws 13, and has an internal shoulder 14 and an outwardly disposed end flange 15. The receiver section 12 is dimensioned to receive the upper end of a tubular pile in the form of a length of pipe and subject to the variations in both inside and outside dimensions that the commercial production of such pipe entails. Piles of different size may be used with the smallest being represented by the pile 16. In order for the pile 16 to be used an adapter sleeve 12A is used. The sleeve 12 has a flange A attached to the fiange 15 as by screws 17.

A cylinder 18, provided with an integral, upper end wall 19 having a central bore 19A, is dimensioned to fit the lower end of the clamp section 10 and includes a lower end flange 20 engaged by the fiange 21 of the cylinder head 22 which has an axial bore 23. The cylinder head 22 is dimensioned to fit the cylinder 18 and an O-ring 24 provides a seal therebetween. Screws 25 extend through the flangcs 20 and 21 and into the clamp section 10 and the proximate faces of its flange 11 and of the receiver section 12 are recessed to accommodate those flanges.

A piston 26 within the cylinder 18 has an O-ring seal 27 for scaling engagement therewith and includes an axial, lower end portion 28 slidably extending through the lower cylinder and wall bore 23 in which there is an O-ring seal 29. The piston 25 also has an axial, upper end portion 30 slidably extending through the cylinder and wall bore 19A in which there is an O-ring seal 31.

The receiver section 12 has conduits 32 and 33 effecting communication between the side wall and the upper face thereof under the flange 21. Where the conduits 32 and 33 open through the side wall, they are counterbored to receive coupling elements 34 and 35, respectively. Each of the coupling elements is preferably of the type having a normally closed check valve which s opened when a conplemental coupling element 36 of the delivery line 37 from the source, not shown, of fluid under pressure or the complemental coupling element 38 of the return line 39 is attached thereto. As the coupling elements 34, and 36 and 38 are conventional, they are not detailed. With any coupling, its release is usually attended by a slight pressure loss and, for that' reason, the conduit 32 has a branch 32B opening into a chamber 32C threaded to receive the plug 32D that may be advanced therein to compensate for the pressure loss.

It is preferred that the elements 34, 35 be located close to each other so that the lines 37 and 39 may be quickly attached to or removed from either one of them.

The conduit 32 opens into a conduit 40 effecting communication between the lower face of the flange 21 and the upper surface of the cylinder head 22 thereof to enable a fluid under pressure to be delivered to or returned from the under side of the piston 26, the junction of the conduits 32 and 40 being sealed as at 32A. The conduit 33 is in communication, via a port 41 through the flange 21, with a conduit 42 between the flange 20 and the cylinder 18 adjacent its end wall 19 thereby to enable fluid under pressure to be delivered or returned from the upper side of the piston 26, the junction of the conduits 33 and 42 and the port 41 being sealed as at 41A. A vent passage 43 through the cylinder end wall 19 is closed by a plug 44 and a vent 45, effecting communication between verse rib 53 shown as entrant of a slotted bolt lock 54 provided with splines 55 entrant of grooves 56 in the upper end of the bore 48. The bolt lock receives a spring 57 backed as by a disc 58 held in place by a detachable retainer 59.

The lower end of the bolt 52 passes -loosely through a bore 60 in the bell-shaped ram head 61 and is threaded to receive the nut 62 for clamping the spherical Washer 63 against the concave seat 64 in the under surface of the ram head 61. The end of the bolt 52 has a transverse rib 65 to facilitate the assembly of the clamp.

The ram head 61 is shown as having a series of slideways 66 shown as extending from top-to-bottom of its outer face and closed at their bottom ends by a retaning ring 67 attached to the open end of the head 61. The slideways 66 have rearwardly and upwardly inclined inner walls 68. A wedge 69 is provided for each slideway 66 and each wedge 69 has its inner wall 70 rearwardly and upwardly inclined and the mutually engaged faces may be coated, if desired. The inclination of the engaged walls is shown as such that the knurled contact faces of the wedge inserts 71 are parallel to the axis of the clamp. Each wedge insert 71 is confined in a dovetail slot 72 extending upwardly from a bottom shoulder 73 and opening into an annular groove 74 which receives a wedge retaining ring 75.

In use, the clamp is positioned so that a pile end enters the receiver 12 and the ram head 61 enters the pile as the mandrel extension is moved downwardly relative to the pile. Because of the nature of the connection between the ram head 61 and the ram stem, the ram head is loose and its axs is universally adjustable relative to that of the stem. To facilitate the entry of the pile between the ram head 61 and the receiver 12, the retaining ring 67 has downwardly disposed, inwardly tapering projections 76 and a slceve 77 is attached to the flange 15, the slceve 77 having a downwardly and outwardly tapering inner face 78. Like faces of the receiver section 12 and of the receiver insert 12A are indicated at 79 and 80, respectively. Fluid under pressure is then admitted under the' piston 26 thus forcing the ram head 61 upwardly with attendant seating of the wedges 69 against the shoulder 14 and their outward movement to distort the pileand lock it securely to the receiver 10 so that it may be driven or withdrawn.

When the pile is driven, the clamp is then detached by attaching the lines so as to deliver fluid under pressure above the piston 26 and to return to source the entrappcd fluid under the piston 26. The carrier s then forced downwardly to free the wedges 69 but the use of means for positively disengaging them from the pile is desirable. Such disengagement is effected by channeling the sideS of the wedges 69 to provide faces 81 parallel to the wedge walls 70. The ram head 61 carries radially disposed bolts 82 between each two Channels and these support a plate 83. Each plate 83 overlies the adjacent wedge faces 81 so that the downward movement of the ram head 61 results in an inward pull on the wedges 69.

In the embodiment shown in the drawings, a larger pile may be used by removing the sleeves 12A and 77 and size changes may obviously be etfected by means of removable shims 69A for the wedges as shown in FIGURE 5.

The embodiment of the nvention, illustrated by FIG- URES 6-10 is generally similar to that just described and hence its description is not detailed except as to important structural ditferences and the reference numerals that indicate corresponding parts are distinguished by the sufix E.

One important difference is that each of the conduits 32E and 33E includes a generally indicated valve 84. The valves 84 are identical and that for the conduit 32E is shown in detail in FIGURE 10 and includes a body 85 bolted at one end to the receiver section 12E with its bore 86 in communication with the conduit 32E and surrounded- &2273483 bya seal 87 of the O-ring type. The bore 86 is divided by an intersectng bore 88 in which there is a rotatable valve element 89 provided with a handle 90 enabling the element 89 to be turned from a position in which it blocks the flow of liquid from end-to-endof the bore 86 into a position in which its passageway 91 is positioned to make such a flow possible.

The outer end of each body is enlarged and has an nteriorly threaded socket 92 into which a coupling element, the element 34E in FIGURE lOA, is threaded against an interposed seal 93 shown as of the O-ring type. A similar ring 94 is disposed between the bore 88 and the rotatable valve element 89 which also carries a like seal 95 surrounding, when the valve is closed, the proximate end of that part of the bore 86 that is always in connection with the conduit 32E.

The body 85 of each valve 84 has a spring pressed detent 96 yieldably holding the valve element 89 in either its closed or its open position thus to prevent accidental valve movement while enabling both the conduit 32E and the conduit 33E to be positively closed before detaching the appropriate one of the couplng elements 34E or 35E, therefrom.

It will be noted that the valves 84 from the two conduits are spaced approximately 180 apart and that both the vent 43E and the vent 45E extend lengthwise through the end portion 28E of the piston 26E with the open end of the vent 43E opening through the upper face of the piston 26E and the open end of the vent 45E opening through the lower face thereof.

In practice, the cylinder chambers are filled with oil with air being bled through the vents 44E and 45E before the assembled ram is attached and the valves 84 ensure that no oil can escape from either side of the piston 26E when the lines are disconnected therefrom.

Another important feature of the embodiment of the invention illustrated by FIGURES 6-10 is that the ring 75E,*which retainsthe wedges 69E, is an integral part of the receiver section 12E thereof thus` to better withstand the stresses and strains placed thereon during use of the clamp. v The .interier of the receiver section 12E, below the retaining ring 75E is shown as having a series of annular grooves 97 thus to make possible a better grip on the outside of the pile when held by the clamp and the wedges 69E are shown as having integral roughened surfaces 98.

In FIGURES 11-14, there is shown an embodiment of the invention for use with a generally indicated pile 99 of H-shaped cross section having its web 100 cut away as at 101. The clamp, like that disclosed in FIGURES 6-10 is so similar to that illustrated in FIGURES l-S, that it is not described in detail except as to important structural ditferences and the reference numerals indicating corresponding parts are distinguished by the sufix F.

The receiver section 12F is of rectangular shape as is the ram head 61F which enters between the side walls 102 of the pile 99 and has removable adapter inserts 103, on one pair of opposite sides, slideways 66F for the wallengaging wedges 69F. The wedges 69F are held in place by a retainer 75F which is in the form of an inturned flange at the lower end of a sleeve 104 having a flange 105 at its upper end attached by screws 106 to the receiver section 12F. Each of the other pair of opposite sides of the ram head 61F has a vertical channel 107 receiving a guide 108 fixed on the inner surface of the receiver section 12F by bolts`109 and flanked by removable adapter inserts 110.

i From the foregoing, it will be appreciated that clamps in accordance with the invention are well adapted to meet the requrements and enable ples and other earth entering elements to be securely gripped and positively released.

We claim:

1. In a clamp for use in attaching an earth enterng element to the driving member of a driver, the element having end portions disposed to enable them to be distorted in a direction away from each other and clamped against hacking surfaces, a downwardly opening receiver section dimensioned to freely receive the upper end of said element and to provide such hacking surfaces, a doubleacting ram including universally adjustable supporting and actuating means within said receiver section, a plurality of wedges attached to said means for vertical sliding movement relative thereto, said wedges and said means having mutually engaged upwardly and inwardly inclined surfaces to efiect outward movement of said wedges from inner positions thereof on upward movement of said means relative to said wedges, said wedges, in their inner positions, being disposed in clamping relation to said portions as said element end enters said receiver section.

2. In a clamp for use in attaching an earth enterng element to the driving member of a driver, the element having end portions disposed to enable them to be distorted in a direction away from each other, an upper housing section, a lower, downwardly opening receiver section dimensioned to freely receive the upper end of said element, a double-acting ram within said housing section and including a ram head within said receiver section, and a plurality of wedges attached to said ram head for Vertical sliding movement relative thereto, said wedges and said ram head having first mutually engaged, upwardly and inwardly inclined surfaces, the ram head surfaces underlying said wedge surfaces thus to eect outward movement of said wedges from inner positions thereof on upward movement of said ram head relative to said wedges, said wedges, in their inner positions enterng said element end as said element end enters said receiver section, and said ram head and said wedges having second surfaces which are downwardly and outwardly inclined, the second head surfaces being spaced outwardly in overlying relationship to said second wedge surfaces with the distance therebetween decreasing as said wedges move outwardly into element clamping position, subsequent downward movement of said head resulting in the engagement of said second head surfaces with said second wedge surfaces and the inward movement of the wedges if the wedges have adhered to the element.

3. In a clamp for use in attaching an earth enterng element to the driving member of a driver, the element having end portions disposed to enable them to be distorted in a direction away from each other, an upper housing section, a lower, downwardly opening receiver section dimensioned to freely receive the upper end of said element, a double-acting ram within said housing section and including a ram head within said receiver section, and provided with a series of upwardly and inwardly inclined, vertical slideways and a plurality of wedges, one in each slideway, each wedge having an upwardly and inwardly inclined, slideway engaging wall, thus to effect outward movement of said wedges from inner positions thereof on upward movement of said ram head relative to said wedges, said wedges, in their inner positions enterng said element end as said element end enters said receiver section, the adjacent edges of adjacent wedges including downwardly and outwardly inclined shoulders, anda series of plates carried by said ram head, each plate being spaced outwardly in ove'lying relationship to the 'adjacent shoulders of adjacent wedges with the distance therebetween decreasing as said wedges move outwardly into element clamping position, subsequent downward movement of said head resulting in the engagement of saidi plates with said shoulders thereby to force the wedges inwardly if they have adhered to the element.

4. In a clamp for use in attaching an earth enterng element to the driving member of a driver, the element having end portions disposed to enable them to be distorted in a direction away from each other, an upper housing section, a lower, downwardly opening receiver section dimensioned to freely receive the upper end of said element, a double-acting ram within said housing section and including a ram head within said receiver section, and a plurality of wedges on said ram head for vertical sliding movement relative thereto, said wedges and said ram head having mutually engaged, upwardly and inwardly inclined surfaces to effect outward movement of said wedges from inner positions thereof on upward movement of said ram head relative to said wedges, said wedges, in their inner positions entering said element end as said element end enters said receiver section, and a retainer carried by said lower section and connected to said wedges to hold them against vertical movement.

5. In a clamp for use in attaching an earth entering element to the driving member of a driver, the element having end portions disposed to enable them to be distorted in a direction away from each other, an upper housing section provided with a flange at its lower end, a lower, downwardly opening receiver section dimensioned to freely receive the upper end of said element and attached to said flange, a double-acting ram including a downwardly opening cylinder within said housing section provided with an end flange, and a cylinder head, said cylinder flange and cylinder head being clamped between said received section and said housing flange, said ram also including a ram head within said receiver section, and a plurality of wedges attached to said ram head for vertical sliding movement relative thereto, said wedges and said ram head having mutually engaged upwardly and inwardly inclined surfaces to eflect outward movement of said wed ges from inner positions thereof on upward movement of said ram head relative to said wedges, said wedges, in their inner positions, entering said element end as said element end enters said receiver section.

6. In a clamp for use in attaching an earth entering element to the driving member 'of a driver, the element having end portions disposed to enable them to be distorted in a direction away from each other, an upper housing section, a lower, downwardly opening receiver section dimensioned to freely receive the upper end of said element, a double-acting ram within said housing section and including a ram head within said receiver section, a plurality of wedges attached to said ram head for Vertical sliding movement relative thereto, said wedges and said ram head having mutually engaged upwardly and inwardly inclined surfaces to eifect outward movement of said wedges from inner positions thereof on upward movement of said ram head relative to said wedges, said wedges, in their inner positions, entering said element end as said element end enters said receiver section, and centering means to vary the spacing between the element engaging faces of the wedges and the receiver section.

7. The clamp of claim 6 in which the means for varying the spacing comprises a sleeve in the receiver section detachably attached thereto.

8. The clamp of claim 6 in which the means for varying the spacing comprises inserts attached to the inner surface of the lower housing section.

9. In a clamp for use in attaching an earth entering element to the driving member of a driver, an upper housing section, a lower section attached to said housing section, a double-acting ram within said housing section and including a ram within said lower section, and a plurality of wedges attached to said ram head for vertical sliding movement relative thereto, a downwardly opening cylinder within said housing section, said cylinder including a flange at its open end, a cylinder head, said flange and said cylinder head being clamped between said sections, the piston of said ram including a stern slidably extending through said head and having an axial passage extending therethrough, a ram head within said lower section, said ram head having an axial bore, a bolt extending freely through said stern and said axial bore, and a nut threaded on said bolt and loosely locking said ram head to said stem.

10. In a clamp for use in attaching an earth enteringelement to the driving member of a driveryanupper housing section, a lower section attaching to said housing section and including a ram within said lower section and a plurality of wedges attached to said ram head for vertical sliding movement relative thereto, a double-acting ram within said housing section, a downwardly opening cylinder within said housing section, said cylinder including a flange at its open end, a cylinder head, said flange and said cylinder head being clamped between said sections, the piston of said ram including a stem including upwardly and downwardly disposed portions, said stern having an axial passage extending therethrough, said upwardly disposed portion being slidably supported by said cylinder and said downwardly disposed portion being slidably supported by said cylinder head, a ram head within said lower section, said ram head having an axial bore, a bolt extending freely through said stem and said axial bore, and a nut threaded on said bolt and losely locking said ram head to said stem.

11. In a clamp for use in attaching an earth entering element to the driving member of a driver, the element having end portions disposed to enable them to be distorted in a direction away from each other and clamped against hacking surfaces, a downwardly opening receiver section dimensioned to freely receive the upper end of said element and to provide such hacking surfaces, a double-acting ram including supporting and actuating means within said receiver section, said means being loosely connected to said ram and universally adjustable relative thereto, a plurality of wedges attached to said means for vertical sliding movement relative thereto, said wedges and said means having mutually engaged upwardly and inwardly inclined surfaces to effect outward movement of said wedges from inner positions thereof on upward movement of said means relative to said wedges,- said wedges, in their inner positions, being disposed in clamping relation to said portions as said element end enters said receiver section.

12. In a clamp for use in attaching an earth entering element to the driving element of a driver, a housing section, a double-acting ram within said section, a lower section detachably attached to said housing section the piston of said ram including a stem, a ram head within said lower section, a plurality of wedges attached to said ram head for vertical sliding movement relative thereto and means connecting said ram head to said stem, said means being of a universally adjustable type and enabling the angular axis of said ram head to be varied relative to the axis of said stem.

13. In a clamp for use in attaching an earth entering element to the -driving member of a driver, an upper housing section, a lower section attached to said housing section, a double-acting ram within said housing section, the piston of said ram including a stem. having an axial passage extending therethrough, said passage having a concave seat at its upper end, a ram head within said lower section, a plurality of wedges attached to said ram head for vertical sliding movement relative thereto said ram head having an axial bore provided with a concave seat at its lower end, a bolt extending freely through said axial passage and said axial bore, said bolt having a convex head in engagement with said passage seat, means in the upper end of said passage holding said bolt against turning, a convex Washer in engagement with said bore seat, and a nut threaded on said bolt against said Washer and loosely locking said ram head against the lower end of said stem.

14. The clamp of claim 13 in which the upper end of said bolt is in the form of a rib and the bolt holding means including a lock slidably splined in the passage seat, a removable closure Secured in the passage seat, and a compression spring interposed between the lock and theseat.

15. In a clamp for use in attaching an earth entering element to the driving member of a driver, an upper hous- V g' section, a' lower Ieceiver section attached to said &2273483 housing section, a double-acting ram including a downwardly opening cylinder within said housing section, said cylinder including a flange at its open end, a cylinder head, said flange and said head being clamped between said sections, said lower receiver section having first and second conduits, both etecting communication between the side and the upper surface of said lower section, said cylinder head having a conduit effecting communication between the first conduit and the upper surface of said cylinder head said cylinder having a conduit efiecting communication with its interior adjacent its upwr end and the undersurface of its flange, and said cylinder head having a passage eifecting communication between the cylinder conduit and the second receiver conduit.

16. In a clamp for use in attaching an earth entering element to the driving member of a driver, an upper housing section, a lower receiver section attached to said housing section, a double-acting ram including a downwardly opening cylinder within said housing section, said cylinder including a flange at its open end, a cylinder head, said flange and said head being clamped between said sections, said lower receiver section having first and second conduits, both effecting communication between the side and the upper surface of said lower section, said cylinder head having a conduit efiecting communication between the first conduit and the upper surface of said cylinder head, said cylinder having a conduit effecting communication with its interior surface adjacent its upper end and the under surface of its flange, and said cylinder head having a passage efecting communication between the cylinder conduit and the second receiver conduit, the pisten of said ram including a stem and separate means to vent the interior of the cylinder on both sides of the piston, said means being vent passages, each including a removable closure, at least one such vent passage extending lengthwise of the stern and opening through the lower end thereof.

References Cited bythe Examiner UNITED STATES PATENTS 1,246,333 11/1917 Sclatter 285-417 1,425,382 8/1922 Hatheway 285-324 1,677,332 7/ 1928 Clayton 285-324 1,754,344 4/1930 Alo 294-8625 1,825,026 9/1931 Thomas 29 1-8625 1,897,561 2/1933 Manucci et al. 294-94 2,952,295 9/ 1960 Marinovich et al. 294-88 FOREIGN PATENTS 81,801 6/ 1956 Netherlands.

M. HENSON WOOD, JR., Pr'mary Exam'ner.

ANDRES I-I. NIELSEN, SAMUEL F. COLEMAN,

Examners. 

1. IN A CLAMP FOR USE IN ATTACHING AN EARTH ENTERING ELEMENT TO THE DRIVING MEMBER OF A DRIVE, THE ELEMENT HAVING END PORTIONS DISPOSED TO ENABLE THEM TO BE DISTORTED IN A DIRECTION AWAY FROM EACH OTHER AND CLAMPED AGAINST BACKING SURFACES, A DOWNWARDLY OPENING RECEIVER SECTION DIMENSIONED TO FREELY RECEIVE THE UPPER END OF SAID ELEMENT AND TO PROVIDE SUCH BACKING SURFACES, A DOUBLEACTING RAM INCLUDING UNIVERSALLY ADJUSTABLE SUPPORTING AND ACTUATING MEANS WITHIN SAID RECEIVER SECTION, A PLURALITY 